Apparatus and method for positioning warp sheds

ABSTRACT

During weaving of a fabric and during reciprocation of a race comb for a gripper shuttle along a part-circular path with the slay, reciprocating guide means move a fabric portion with an open warp shed transversely to the path of the race comb so that the race comb is entered into the warp shed near the front position thereof, and is located substantially at the center of the warp shed when arriving at its rear position in which a gripper shuttle is picked through the race comb and warp shed.

United States Patent Inventor Zdenek Rambousek Liberec, CzechoslovakiaApp]. No. 829,374 Filed June 2,1969 Patented May 25, 1971 AssigneeElitex, Zavody Textilniho Strojirenstvi Liberec, Czechoslovakia PriorityJune 3, 1968 Czechoslovakia PV4069-68 APPARATUS AND METHOD FORPOSITIONING WARP SHEDS 7 Claims, 7 Drawing Figs.

U.S. Cl 139/190,

139/291 Int. Cl D03d 49/00 Field of Search 139/188,

[56] References Cited UNITED STATES PATENTS 631,561 8/1899 Claviez 1.139/291 3,424,206 1/1969 Rambousek et al. 139/188 FOREIGN PATENTS738,984 10/1932 France 139/291 Primary Examiner-l-lenry S. JaudonAttorney-Michael S. Striker ABSTRACT: During weaving of a fabric andduring reciprocation of a race comb for a gripper shuttle along apart-circular path with the slay, reciprocating guide means move afabric portion with an open warp shed transversely to the path of therace comb so that the race comb is entered into the warp shed near thefrom position thereof, and is located substantially at the center of thewarp shed when arriving at its rear position in which a gripper shuttleis picked through the race comb and warp shed.

Patented May 25, 1971 3,580,292

2 Sheets-Sheet 2 L INVENTOR Z flan/30mm ATTORNEY APPARATUS ANDMETHOD FORPOSITIONING WARP I SHEDS BACKGROUND OF THE INVENTION In gripper shuttlelooms, and in similar looms, gripper shuttles are picked through a racecomb which includes a series of race elements which enter between thewarp threads of a warp into the warp shed so that the gripper shuttlecan be picked through the warp shed while being guided in the race combacross the warp shed.

The race comb is moved by the slay into the open warp shed beforepicking, and moves out of the warp shed due to the movement of the slayafter the picking of the weft so that the newly inserted weft can beheat into the fell of the fabric by a reed mounted on the slay. Theduration of each pick depends to certain extent on the time required forthe race comb to be moved by the slay into the warp shed to the positionrequired for guiding the gripper shuttle in the warp shed across thesame. The guiding of the gripper shuttle during the pick by a race combis preferable to the guiding of the shuttle by the warps forming theshed.

In apparatus according to the prior art, the race comb is secured to theslay or batten and moves abouta circular path whose center coincideswith the shaft or pivot on which the slay is supported for angularrocking movement.

It has been found that movement of the race comb along a circular pathhas disadvantages since the race comb moves into the shed in such arelative position that the pick must be performed relatively late sothat the time available for the picking operation itself is shortened.On the other hand, the race comb moving with the slay leaves the shedcompletely directly before the beating of the weft by the reed, whichmay cause a streaky appearance of the fabric particularly in the warpdirection since the late removal of the race comb from the warp sheddisturbs the regular distribution of the warp threads which cannotassume again the regular parallel position before the respectiveinserted weft is beaten by the reed and the warp shed is closed.

In view of the above disadvantage of a circular path for the race comb,it would be desirable to move the race comb along a path which is notcircular, and which would make it possible for the race comb to enterthe shed as soon as possible, and to remain there as long as possible,but leaving the warp shed again early enough before the beating of theweft by the reed.

In accordance with known apparatus, the race comb is mounted on the slayfor independent movement, and when the slay is moved to its rearposition, the race comb is moved in an additional motion into the shed,while during the movement of the slay with the reed to the frontposition, the race comb is independently withdrawn from the shed, movingrelative to the slay before the reed on the slay beats the weft thread.

This improved system according to the prior art has the disadvantagethat a complex construction is required for mounting the race comb onthe slay, and for operating the race comb relative to the slay.Furthermore, the required independent oscillation of the race combnecessitates a rigid and strong construction of the race comb along theentire width of the loom which can be obtained only under greatdifficulties, and has the disadvantage of increasing the inertial masswhich has to be moved.

It is one object of the invention to overcome the disadvantages of priorart constructions for positioning a race comb in a warp shed, and toprovide an arrangement in which the warp shed is moved relative to thepath of the race comb which is reciprocated by the slay.

Another object of the invention is to provide an arrangement in which bydisplacement of the warp shed, the race combis quickly placed at thecenter of he warp shed, so that sufficient time is available for thepicking of the shuttle.

Another object of the invention is to move the warp shed relative to thecircular path of the race comb so that the shed is withdrawn from therace comb a sufficient time before the beating operation so that theposition of the warp threads is not disturbed in the finished fabric.

SUMMARY OF THE INVENTION With these objects in view, the apparatus ofthe invention positions warp sheds during the weaving of a fabric, andcomprises a slay having a reedand a race comb, and being movable betweena front position and a rear position while the race comb moves along apredetermined path; guide means for guiding the fabric forwardly of thefell of the fabric; and control means operating in timed relation withthe slay for reciprocating the guide means with the fabric and with awarp shed, transversely to the plane of the fabric and toward and awayfrom the path of the race comb.

The reed beats a weft thread into the fell of the fabric in the frontposition, and a shuttle is picked through the race comb in the rearposition of the slay. Due to the displacement of the warp shed by theguide means relative to the path of the race comb, the race comb entersand leaves the warp shed a predetermined distance from the frontposition and from the fell of the fabric, so that the warps are not in adisturbed condition when the reed beats the weft thread. On the otherhand, the displacement of the warp shed places the race combsubstantially at the center of the warp shed when the slay has moved tothe rear position so that the race comb can guide a picked shuttleacross and through the warp shed.

In the preferred embodiment of the invention the guide means forms aslot for guiding the fabric in a substantially horizontal working plane,and the slay is mounted for angular rocking movement so that the reedand the race comb move along a substantially horizontal portion of acircle located under the working plane of the fabric. The control meansinclude a cam rotating in synchronism with the angular rocking movementof the slay, and cam follower means connected with the guide means forraising and lowering the same.

A method according to the present invention comprises the steps ofreciprocating a race comb along a predetermined path between front andrear positions, and moving, during reciprocation of the race comb, thefabric with a warp shed transversely to the path from a first positionin which a portion of he warp shed near the fell crosses the path sothat the race comb is entered into the warp shed near the front positionthereof, to a second position in which the race comb is locatedsubstantially at the center of the warp shed while being on the pathnear the rear position thereof whereby a shuttle can be picked along therace comb across the warp shed, and finally back to the first positionso that a portion of the warp shed crosses the path again and the racecomb is left outside of he warp shed spaced a predetermined distancefrom the front position thereof and from the fell of he fabric.

It will be seen that in accordance with the invention, the position ofthe warp shed near the fell of the fabric is varied in accordance with alaw determined by the cam controlling the guide means in order to obtainproper and desired positioning of the race comb in relation to the warpshed due to the combination of the motion of the race comb along thecircular path with an up-and-down motion of the warp shed.

The timing is such that the warp shed is moved downward when the slayand the race comb move toward the rear, and upward when the slay andrace comb move to a front position in which the reed beats up the weftso that the separation of the race comb from the warp shed isaccelerated.

The novel features which are considered as characteristic for theinvention are set forth in particular in the appended claims. Theinvention itself, however, both as to its construction and its method ofoperation, together with additional objects and advantages thereof, willbe best understood from the following description of specificembodiments when read in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWING FIG. I is a fragmentaryschematiccross-sectional view illustrating a portion of a loom providedwith the apparatus of the invention;

FIG. 2 is fragmentary schematic view illustrating the rela tivemovements between the race comb and the warp shed; and

FIGS. 3 to 7 are fragmentary schematic views illustrating successiveoperational positions of the apparatus of FIG. I during the displacementof a warp shed, and movement of the race comb along a circular path.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings,and particularly to FIG. ll, journals 2 support the arms 3 of a slay 4for angular rocking movement on lateral walls 1, of which only one isshown. The slay 4 carries a reed 5 and a race comb 6 which consists of arow of recessed elements 23, see FIG. 2, which form a race for a grippershuttle 7 together with the reed 5. The slay 4 is movable between afront position in which reed 5 beats the weft thread into the fell I3 ofthe fabric I2, and a rear position 5, see also FIG. 2, in which theshuttle is picked.

Forwardly of the fell 13 of the fabric, a pair of horizontal parallelguide bars I4 and 15 form between each other a gap through which fabric12 passes to the breast beam 16 and over the same to winding rollers andto the cloth beam 17 on which the fabric 12 is wound up as new fabric iswoven at the fell of the fabric by weft thread inserted into a warp shedformed by heddles of warp 8 and 9.

At both ends of breast beam 16, brackets and pivots 19 provided whichrespectively support carrier levers 18 on both sides of the fabric andloom. Guide bars 14 and are secured at the ends thereof to the twolevers 18 so that warps 8 and 9, and the warp shed 11 formed by the sameare moved up and down when guide members 14, I5 move between theposition shown in solid lines, and the position shown in broken lines inFIG. 1.

At least one of carrier levers 18 support a cam follower roller 21 whichis urged by a spring 22 acting on lever I8 into engagement with theperipheral cam track of a rotary cam which is driven in synchronism withthe angular rocking movement ofslay 3, 4.

In addition to the guide bars 14 and 15, the fabric is guided in aconventional manner by stretching means, not shown.

During the rocking movement of slay 4, the center of the recessedportions 23 of the elements of race comb 6 move along an are 24 of acircle which is substantially horizontal, and located below the plane offabric 112 which is schematically indicated by thin line 12a in FIG. I.

The rotary earns 20 transmit through cam follower rollers 21 and carrierlevers I8, a swinging up-and-down motion to the guide bars 14 and 15.The displacement of the guide bars l4, 15 from the position shown insolid lines in FIG. 1 to the position shown in broken lines, willdisplace the respective warp shed. FIG. 2 schematically illustrates thewarp shed II as if it would not move so that during the angular movementof race comb 6 with slay 4, the upper end of the race comb 6 moves alongan imaginary path 7a, and the center of the recessed portion 23 movesalong an imaginary line 7b in relation to the warps 8 and 9. In otherwords, in order to obtain the relative position between the race comb 6and the warp shed 11 without displacement of the warp shed in accordancewith the invention by the guide means l4, 15, it would be necessary tomove the race comb along the path indicated by lines 7a, 7b, which pathwould no longer be circular as is the actual path 24 of the center ofthe depressed portion of the race comb 6.

FIG. 2 shows a distance b between the fell of the fabric 13 and a pointof the imaginary path at which the upper end of comb 6 enters the warpshed II. The distance b between the fell 13 of the fabric and a point ofthe path 7b of the center of the recessed portion 23 indicates theposition which the depressed guide portions 23 ofthe race comb 6 assumeat the center of the warp shed 11 between warps 8 and 9 for the pickingof the shuttle. It will be understood that actually comb 6 moves alongthe circular path 24, and is placed in the desired positions relative towarp shed II only due to the downward movement of the warp shed by guidemembers 14 and 15.

In FIGS. 3 to 7, the actual positions of thewarp shed l1, and of thewarps 8 and 9 are shown in solid lines, while FIGS. 4 to 7 illustrate inbroken lines 811 and 9a an invariable position of the warp shed inaccordance with the prior art so that the displacement of the warp shedcan be more clearly understood. Warps 8 and 9 of shed II define theangle a, while warps 8a and 9a define the angle a.

The initial basic position of the apparatus is assumed to be theposition shown in FIGS. 1, 2 and 3 in which the reed beats the weftthread into the fell of the fabric 13. In this position, control cammeans 20 raise the guide means 18, I4 and 15 to the highest positionwhile the heddles 10 fully open the warp shed the angle a. The race comb6 is located below fabric I2 in the left end position of slay 4. In thisposition of the apparatus, the shuttle is located in the shuttle box atone side of the loom, not shown.

During movement of slay'4 from the front beat up position toward itsrear position, race comb 6 moves along the horizontal portion of acircular path 24 but at the same time, fabric 12, with warp shed llbegins to move downward due to the downward movement of guide bars 14and 15, transverse to the path 24 and relative to the same and to racecomb 6. In FIG. 4, guide bars 14 and 15 have moved the fabric 12 withthe warp shed ill a distance a down so that the fell of the fabric hasmoved to the position 13 downward, while comb 6 has moved in clockwisedirection along path 24 to a position in which the upper edge 25 thereofhas entered the warp shed ll. Due to the downward displacement of thewarp shed, the upper edge 25 sooner enters the warp shed and the guideelements 23 sooner pass between warp sheds of warp 9 than would be thecase if the warp shed would remain in the position indicated by thebroken lines 8a and 9a. However, the upper ends 25 of the elements 23 ofrace comb 6 enter the warp shed a safe distance b, from the last weftthread at the fell 13 of the fabric so that the last weft thread cannotbe caught and disturbed.

In FIG. 5, guide bars 14 and 115 have moved downward the distance a sothat the fell of the fabric is located at 13''. Race comb 6 hascontinued its movement along the circular path 24, and the centers ofthe depressed portions of guide elements 23 which are located on thecircular path 24, are also located at the center of the warp shed llspaced the same distance from warps 8 and 9. If the warp shed hadremained in the initial position indicated by broken lines 8a and 9a,the race of race comb 6 would not be located at the center of the warpshed equally spaced from warps 8a and 9a. Consequently, in thearrangement of the invention, the race of the race comb 6 will be soonerin a position permitting the picking of the shuttle 7, as compared withthe prior art construction in which the path 24 would not even belocated at the center of the warp shed since the depressed guideportions 23 forming the race would not penetrate deeply enough into thewarp shed 3a, remaining in its initial position. In the position of FIG.5, the center of the depressed race portions 23 is located spaced thedistance b from the fell of the fabric, as shown in FIG. 2. The properplacing of the race comb 6 in the shuttle guiding central position inthe warp shed requires a downward movement of the warp shed for thedistance a As shown in FIG. 1, cam 20 has such a shape that downwardmovement of the fabric and warp shed is stopped while reed 5 is in itsrear end position-Shuttle 7 has traversed the warp shed, and the warps 8and 9 have been moved by the heddles 10 to an almost closed positiondefining the angle B. The broken lines 8a and 90 define the angle [3,and show the position of the warp shed if the same had remained in itsinitial position shown in FIG. 2. It will be seen that the race of racecomb 6 and the circular path 24 are still located in the smaller warp11, which vwould not be the case if the warp shed had remained in itsinitial position 8a, 9a.

FIG. 7 shows race comb 6 and reed 5 during the return movement towardthe front position, while cam has raised guide bars 14 and 15 to aposition in which a fell of the fabric is located at 13' spaced againthe distance a from the initial position 13 of the fell of the fabric.The upper end of race comb 6 has just left the warp shed 11 passingbetween the warp threads of warp 8 a sufficient distance from the fell13 so that the warp threads will not be disturbed when the reed 5 beatsthe inserted weft thread into the fell of the fabric. When the operationis continued, the fabric is raised to its initial position shown in FIG.3, and the warp shed 11 is closed and a new warp shed opened so that theabove-described operations can be repeated.

It will be seen-that, while a minimum safe distance b should bemaintained between the fell of the fabric and the point where the upperedge of the race comb 6 enters and leaves the warp shed, the race of therace comb 6 should reach a central position in the warp shed at adistance [1 from the fell 13, which should be as small as possible sincethis makes more time available for the picking of the shuttle.

During the movement of the slay with the race comb toward the rearposition, it is sufficient to maintain the race of race comb 6 andshuttle 7 substantially at the center plane of the warp shed 11. Duringmovement of slay 4 toward the front position in which the weft thread isbeaten up, it is necessary to accelerate the movement of the warp-shedso that the race comb 6 is separated from warp shed ll during movementfrom the position shown in FIG. 6 to the position shown in FIG. 2 sothat the upper edge 25 of the race comb 6 is located outside of the shedspaced the safe distance b from the fell 13 and cannot cause streaksextending in warp direction in the finished fabric.

In order to obtain a displacement of the fell 13 with the warp shed 11in downward direction irrespective of the number of warp threads in theupper and lower warps 8 and 9, the fabric 12 should be guided by the gapbetween guide bars 14 and 15 as closely as possible to the fell 13. Thedownward movement of the guide bars 14 and 15 takes place due to theaction of springs 22 acting on carrier levers l8 and urging cam followerroller 21 against the track of rotary cam 20.

While FIG. 1 illustrates the preferred embodiment of the invention inwhich a rotary cam 20 is driven in synchronism with a rocking angularmotion of slay means 3, 4, which is obtained by transmission meansconnecting the shaft of cam 20 and also the slay with a drive motor, itis also possible to mount cam fingers on the front side of the slay 4 onwhich cam follower rollers 21 roll during angular rocking movement ofslay 4 with the cam fingers, not shown. It is also possible to providelink ages between slay 4 and carrier levers 18, and it will beunderstood that irrespective of which control system is used for raisingand lowering the guide bars 14 and 15, the operation must take place insynchronism with the angular rocking movement of the slay. In certainlooms the guiding means for the fabric are combined with stretchingmeans for the fabric, and in some cases it is also possible to provideonly a lower guide bar 14, and to permit the fabric 12 to move down dueto the action of gravity.

It will be understood that each of the elements described above, or twoor more together, may also find a useful application in other types ofarrangements for positioning a race comb relative to a warp sheddiffering from the types described above.

While the invention has been illustrated and described as embodied in amethod and apparatus for positioning warp sheds during the weaving of afabric relative to the path of a race comb for a shuttle, it is notintended to be limited to the details shown, since various modificationsand structural changes may be made without departing in any way from thespirit of the present invention.

What I claim as new and desire to be protected by Letters Patent is setforth in the appended claims.

1. Apparatus for positioning warp sheds during the weaving of a fabric,comprising, in combination, a slay having a reed and race comb, andbeing movable between a front position and a rear position while saidrace comb moves along a predetermined path, so that said reed beats aweft thread into the fell of the fabric in said front position, and sothat a shuttle can be picked through said race comb in said rearposition; heddle means for forming warp sheds at the fell of the fabric;guide means for guiding the fabric forwardly of the fell of the fabricand including first and second guide bars forming a gap for guiding thefabric and extending parallel to the fell of the fabric, carrier meansat the ends of said guide bars including follower means, and supportingmeans mounting said carrier means for movement with said guide memberstransversely to the plane of the fabric; and control means including cammeans operating in synchronism with said slay and controlling saidfollower means with said carrier means and guide bars so that the samereciprocate said fabric and a warp shed transversely to the plane of thefabric and toward and away from said path of said race comb so that dueto the displacement of the warp shed relative to said path of said racecomb, said race comb enters and leaves the warp shed a predetermineddistance from said front position and from the fell of the fabric, andis placed substantially at the center of the warp shed in a shuttleguiding position upon movement of said slay to said rear position.

2. Apparatus as claimed in claim 1 wherein said cam means are mountedfor rotation on said supporting means; wherein said carrier meansinclude lever means rockably mounted on said supporting means; whereinsaid follower means include cam follower roller means cooperating withsaid cam means and mounted on said lever means; wherein saidcontrolmeans include spring means biassing said lever means toward said7 V cam means.

3. Apparatus as claimed in claim 2 wherein said supporting means includea breast beam over which the fabric is guided, two brackets mounted atthe ends of said breast beam, and pivots on said brackets; said levermeans including two levers mounted on said pivots, respectively.

4. Apparatus as claimed in claim 3 wherein said pivots and said guidebars are located at opposite ends of said levers; and wherein said camfollower roller means include rollers mounted on said levers betweensaid opposite ends.

5. Apparatus for positioning warp sheds during the weaving of a fabric,comprising, in combination, a slay having a reed and a race comb, beingmovable between a front position and a rear position while said racecomb moves along a predetermined path, said slay being mounted forangular rocking movement at one end thereof, and said reed. and saidrace comb being mounted on the other end of said slay so that said pathis a substantially horizontal portion of a circle located under saidworking plane so that said reed beats a weft thread into fell of thefabric in said front position, and so that a shuttle can be pickedthrough said race comb in said rear position; heddle means for formingwarp sheds at the fell of the fabric; guide means for guiding the fabricforwardly of the fell of the fabric, said guide means forming a slot forguiding the fabric in a substantially horizontal plane; and controlmeans including cam means for reciprocating said guide means with saidfabric and said warp shed in substantially vertical direction insynchronism with the angular rocking movement of said slay forreciprocating said guide means with said fabric and with a warp shed,transversely to the plane of the fabric and toward and away from saidpath of said race comb so that due to the displacement of the warp shedrelative to said path of said race comb, said race comb enters andleaves the warp shed a predetermined distance from said front positionand from the fell of the fabric, and is placed substantially at thecenter of the warp shed in a shuttle guiding position upon movement ofsaid slay to said rear position.

6. The method of positioning a warp shed during the weaving of a fabric,comprising opening a warp shed at the fell of the fabric; reciprocatinga race comb along a predetermined path between front and rear positions;and moving, during reciprocation of said race comb, said warp shedtransversely to said pathfrom a first position in which a portion ofsaid warp shed near said fell crosses said path so that said race combis entered intosaid warp shed near said front position thereof, to asecond position in which said race comb is located substantially at thecenter of said warp shed while being on said path near said rearposition whereby a shuttle can be picked along said race comb acrosssaid warp shed in said rear position, and finally back to said firstposition so that a portion of said warp shed crosses said path again andsaid

1. Apparatus for positioning warp sheds during the weaving of a fabric,comprising, in combination, a slay having a reed and race comb, andbeing movable between a front position and a rear position while saidrace comb moves along a predetermined path, so that said reed beats aweft thread into the fell of the fabric in said front position, and sothat a shuttle can be picked through said race comb in said rearposition; heddle means for forming warp sheds at the fell of the fabric;guide means for guiding the fabric forwardly of the fell of the fabricand including first and second guide bars forming a gap for guiding thefabric and extending parallel to the fell of the fabric, carrier meansat the ends of said guide bars including follower means, and supportingmeans mounting said carrier means for movement with said guide memberstransversely to the plane of the fabric; and control means including cammeans operating in synchronism with said slay and controlling saidfollower means with said carrier means and guide bars so that the samereciprocate said fabric and a warp shed transversely to the plane of thefabric and toward and away from said path of said race comb so that dueto the displacement of the warp shed relative to said path of said racecomb, said race comb enters and leaves the warp shed a predetermineddistance from said front position and from the fell of the fabric, andis placed substantially at the center of the warp shed in a shuttleguiding position upon movement of said slay to said rear position. 2.Apparatus as claimed in claim 1 wherein said cam means are mounted forrotation on said supporting means; wherein said carrier means includelever means rockably mounted on said supporting means; wherein saidfollower means include cam follower roller means cooperating with saidcam means and mounted on said lever means; wherein said control meansinclude spring means biassing said lever means toward said cam means. 3.Apparatus as claimed in claim 2 wherein said supporting means include abreast beam over which the fabric is guided, two brackets mounted at theends of said breast beam, and pivots on said brackets; said lever meansincluding two levers mounted on said pivots, respectively.
 4. Apparatusas claimed in claim 3 wherein said pivots and said guide bars arelocated at opposite ends of said levers; and wherein said cam followerroller means include rollers mounted on said levers between saidopposite ends.
 5. Apparatus for positioning warp sheds during theweaving of a fabric, comprising, in combination, a slay having a reedand a race comb, being movable between a front position and a rearposition while said race comb moves along a predetermined path, saidslay being mounted for angular rocking movement at one end thereof, andsaid reed and said race comb being mounted on the other end of said slayso that said path is a substantially horizontal portion of a circlelocated under said working plane so that said reed beats a weft threadinto fell of the fabric in said front position, and so that a shuttlecan be picked through said race comb in said rear position; heddle meansfor forming warp sheds at the fell of the fabric; guide means forguiding the fabric forwardly of the fell of the fabric, said guide meansforming a slot for guiding the fabric in a substantially horizontalplane; and control means including cam means for reciprocating saidguide means with said fabric and said warp shed in substantiallyvertical direction in synchronism with the angular rocking movement ofsaid slay for reciprocating said guide means with said fabric and with awarp shed, transversely to the plane of the fabric and toward and awayfrom said path of said race comb so that due to the displacement of thewarp shed relative to said path of said race comb, said race comb entersand leaves the warp shed a predetermined distance from said frontposition and from the fell of the fabric, and is placed substantially atthe center of the warp shed in a shuttle guiding position upon movementof said slay to said rear position.
 6. The method of positioning a warpshed during the weaving of a fabric, comprising opening a warp shed atthe fell of the fabric; reciprocating a race comb along a predeterminedpath between front and rear positions; and moving, during reciprocationof said race comb, said warp shed transversely to said path from a firstposition in which a portion of said warp shed near said fell crossessaid path so that said race comb is entered into said warp shed nearsaid front position thereof, to a second position in which said racecomb is located substantially at the center of said warp shed whilebeing on said path near said rear position whereby a shuttle can bepicked along said race comb across said warp shed in said rear position,and finally back to said first position so that a portion of said warpshed crosses said path again and said race comb is left outside of saidwarp shed spaced a predetermined distance from said front positionthereof and from the fell of the fabric.
 7. The method of claim 6wherein said fabric is located in a horizontal working plane; andwherein said race comb is reciprocated along a substantially horizontalsegment of a circular path; and wherein said fabric is moved insubstantially vertical direction with said warp shed between said firstand second positions.